DUBLIN, Ireland Elan Corp. plc, of Dublin, has submitted a product license application to the FDA for NeuroBloc for the treatment of cervical dystonia.
Paulette Setler, chief scientific officer at Elan, told Bio World International that the company hopes to have the product on the market by the third or fourth quarter of this year. If successful, Elan will be first to market in the U.S. a treatment for cervical dystonia based on botulinum toxin therapy.
Cervical dystonia is a condition of abnormal muscle tone and movement that can result in painful abnormalities of posture and an inability to flex and relax affected neck and shoulder muscles. It currently affects some 50,000 Americans and a similar number of Europeans, according to Elan. The company values the worldwide market the drug will address at more than US$100 million.
So far, the FDA has sanctioned botulinum therapy for ophthalmic indications only. Irvine, Calif.-based Allergan¿s Botox, which is derived from botulinum toxin type A, is approved for treatment of dystonia-associated blepharospasm and strabismus in adults.
NeuroBloc is based on an alternative serotype, botulinum toxin type B, which has a slightly different mechanism of action. Both proteins prevent the release of the neurotransmitter acetylcholine at nerve-muscle junctions, by inhibiting the activity of a protein complex involved in the docking and fusion of synaptic vesicles at the neuronal membrane prior to acetylcholine release.
Botulinum toxin type A acts on a protein called snap-25, whereas the B serotype disrupts a different component of the complex, synaptobrevin. The light chain of the B toxin acts as a zinc-containing protease, Setler said, and has a proteolytic effect on synaptobrevin.
Botulinum therapy is indicated for a large number of neurological conditions, although many of these are not ¿material,¿ Setler said. NeuroBloc ought to be applicable to these other indications as well, she noted. Elan is developing a strategy to address other potential applications of NeuroBloc, but Setler declined to reveal further details. n